The Cross-Polar Cap Saturation in GUMICS-4 During High Solar Wind Driving

It is well known that the Earth's ionospheric cross‐polar cap potential (CPCP) saturates as a response to the solar wind (SW) driver especially when the level of driving is high and the interplanetary magnetic field is oriented southward. Moreover, previous studies have shown that the upstream Alfvén Mach number may be an important factor in the saturation effect. While the CPCP is often viewed as a measure of the SW‐magnetosphere‐ionosphere coupling, the processes associated with the nonlinearity of the coupling remain an open issue. We use fourth edition of the Grand Unified Magnetosphere‐Ionosphere Coupling Simulation (GUMICS‐4) and artificial SW data to mimic weak and strong driving in order to study the CPCP response to a wide range of interplanetary magnetic field magnitudes (3.5–30 nT) and upstream Alfvén Mach number values (1.2–22). The results provide the first overview of the CPCP saturation in GUMICS‐4 and show that the onset of saturation is strongly dependent on the upstream Alfvén Mach number and the physical processes responsible for the saturation effect might take place both in the Earth's magnetosheath and in the upstream SW.

Pulkkinen, T. I.Aalto Univ, Dept Elect & Nanoengn, Espoo, Finland (författare)
Dimmock, Andrew P.Uppsala universitet,Institutet för rymdfysik, Uppsalaavdelningen(Swepub:uu)anddi496 (författare)
Myllys, M.Univ Helsinki, Dept Phys, Helsinki, Finland; CNRS, Lab Phys & Chim Environm & Espace, Orleans, France (författare)
Honkonen, I.Finnish Meteorol Inst, Helsinki, Finland (författare)
Palmroth, M.Univ Helsinki, Dept Phys, Helsinki, Finland (författare)
Aalto Univ, Dept Elect & Nanoengn, Espoo, FinlandInstitutet för rymdfysik, Uppsalaavdelningen (creator_code:org_t)

Ingår i:Journal of Geophysical Research - Space Physics123:5, s. 3320-33322169-93802169-9402

Av författaren/redakt...: Lakka, A.; Pulkkinen, T. I.; Dimmock, Andrew ...; Myllys, M.; Honkonen, I.; Palmroth, M.

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.